The Sun as Observed by SORCE SOLSTICE

Authors: William McClintock, Marty Snow, Gary Rottman, and Tom Woods
Affiliation: LASP, University of Colorado

The SOLar-STellar Irradiance Comparison Experiment (SOLSTICE) on SORCE has been making daily spectral observations of the Sun from 115-300 nm. Careful preflight calibration and in-flight degradation monitoring with stellar irradiances produces absolute irradiance at the 5% level and relative measurements at the 1% level. The ratio of solar to stellar irradiance is an absolute measurement of solar variability that is independent of instrumental degradation. This ratio can be re-measured in future epochs to create an irradiance record spanning centuries.

The wavelength range of SOLSTICE includes the important chromospheric Magnesium II h & k lines as well as Lyman alpha. The SORCE observations extend the observational database of solar variability started by the UARS SOLSTICE, and we will present recent results.